Author Topic: Going to a 130mm reflector from a 70mm refractor  (Read 242 times)

Robert Garcia

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #15 on: January 11, 2018, 02:16:40 PM »
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Well the refractor was a Celestron powerseeker 70AZ which believe it or not showed me some things that I thought weren't possible with such a small scope
The reflector I'm looking at is the Celestron Powerseeker 127EQ, now I know that there are better reflectors out there but I'm short on money right now so I was looking at inexpensive reflectors
I mean I got my refractor for $50 and the reflector is currently $130, surely it should give me clearer and brighter images?
Oh and It was 127mm guys, sorry for saying 130mm, although I don't know if those 3mm will make a significant difference
stay away from the 127 reflector, i'd rather see you get the 114 powerseeker. there is a short tube 130mm orion in the clearance section for 237 complete.

The Orion SpaceProbe 130ST is called a short tube Newtonian because of it's F/5 focal ratio but it is a standard Newtonian with a Parabolic mirror and not a Jones-Bird scope. Jones-Bird scopes are often called short tube Newtonians because they are so short.. In my experience, they are best avoided, they are a compromise design and do not deliver.

The way to identify a Jones-bird telescope is to compare the focal length of the OTA with the length of the OTA. If it's a standard Newtonian, then the focal length and physical length will be about the same. If it's a Jones-Bird, then the focal length will be much longer than the physical length. Typically the scope might have a 1 meter focal length but be less than 500mm, in length.

Jon

scamcackratge

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #16 on: January 13, 2018, 06:39:13 AM »
I picked this Tasco Newtonian up a couple of years ago for $35.00
114mm 900mm fl.
Tube is 34 inches long./865mm.

Similar to Bushnell and some Meades and other brands.
Optics were good, eq mount is okay at lower mags appr. X75 otherwise it's pretty light duty and shaky.
Focusar was a bit stiff but ok after adjusted.
Eyepieces and barlow included were prettycheap, but I have some decent Plossls that really help.
Good for quick grab and go, but could really use a better mount.
Though larger then a 70mm it's really limited for DSO's in the city.
Good for M42, Pleiades ,open clusters, moon Saturn, Jupiter and more.
Can't say I've really seen the GRS on Jupiter though this scope yet.
Sam

bardersgarli

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #17 on: January 13, 2018, 03:33:35 PM »
The Spaceprobe 130 does look like it would be a nice scope. I had a friend from where I used to live pick one up lately. He was pretty set on that style of scope. However, at it's price new I'd probably go toward the XT6 dobsonian.

Another good alternative to the spaceprobe 130 is the Vixen 130mm on a porta II mount. Believe the price was pretty close to the spaceprobe on BHphotovideo.com ...was on sale I think.

I like alt/az mounts but there are advantages to equatorial mounts sometimes.

Kash Dickens

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #18 on: January 17, 2018, 12:34:08 AM »
Why not just get a 6" dob? It's more portable and has a slightly larger aperture and they are easier to use than an equatorial mount, which is what most of these 5" reflectors are.

Paul Nyuon

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #19 on: January 18, 2018, 08:21:58 AM »
I didn't check but, if the 127 is a Bird-Jones I would suggest staying away from it. I have 2 BJ scopesthat I wish I never would have bought. Luckily I bought both cheap. I did get a CG-4 mount with the C6N though. That's what I'm using for the Vixen 130 that will be here Friday.

clicpostreta

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #20 on: January 20, 2018, 06:37:35 PM »
I bought a new Celstron Powerseeker 70AZ a few years back, but the optics were poor compared to a Vixen Space Eye 70 refractor (Vixen's low-end line of refractors) I got used. Couldn't focus sharply on the moon and stars compared to the latter.

I also bought a Celestron Astromaster 130EQ new (not a Bird-Jones), but the optics was just bad, even after I center spotted the primary and collimated it (a few others have also reported getting bad samples of this scope on CN Forum).  Fortunately, my Bushnell Ares 5 (identical to the AWB One Sky) has good optics and the primary mirror came center-spotted.

The Celestron Powerseeker 114EQ comes with good optics, but as others on this thread have mentioned, you'll need to get a better mount for it. My Powerseeker 114 was first mated with an Orion Versago II alt-azimuth I had lying around and currently I use it on the CG3 equatorial mount that came with the Astromaster 130EQ. The latter EQ mount is not as stable as the Orion alt-azimuth, but as long as conditions are wind-free, I get steady, shake-free views with a 6mm EP (150X).

The new Meade Polaris 114EQ, apparently comes with a more substantial mount (EQ2) than the Powerseeker 114's EQ1 and at $169 retail, looks to be the scope to get if funds are limited.

Alejandro Taylor

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #21 on: January 23, 2018, 10:49:50 AM »
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Well the refractor was a Celestron powerseeker 70AZ which believe it or not showed me some things that I thought weren't possible with such a small scope
The reflector I'm looking at is the Celestron Powerseeker 127EQ, now I know that there are better reflectors out there but I'm short on money right now so I was looking at inexpensive reflectors
I mean I got my refractor for $50 and the reflector is currently $130, surely it should give me clearer and brighter images?
Oh and It was 127mm guys, sorry for saying 130mm, although I don't know if those 3mm will make a significant difference

Based on my experience with several 114 and a couple of 150mm shorty Bird-Jones scopes similar to the 127 you would be far better with a full length 114 if money is limited.The Bird-Jones types have poor images at higher powers and are more difficult to properly collimate(adjust the mirrors).The appeal of the Bird-Jones design is the compactness which is an advantage mostly for shipping,storage,and sales-not so much for performance.

You'd be better to do as many have and pick up a used 114f8 full-size from craigslist,ebay,thrift store,or whatever.There are even a couple on ebay for $25 and $35 but pick-up only.A new 114AZ Celestron is also within your budget.The poster above with his Tasco 114 almost certainly will see better views at higher powers than you would with a 127 shorty.I know the view is better in any one of my collection of used(Tasco,Meade,Celestron,Bushnell) 114 full-length f8 than in any of the four 114 Bird-Jones shorty scopes I have looked through.(Yes, I probably do have more scopes than one person "needs".)

There are 130mm reflectors with relatively short tubes and if they are f5 that is fine;such a scope is good for wider field of view and if the mirror is a parabolic can do well for planetary views too.
Also I'd guesstimate the equivalence of a 127-130 reflector to a 110 refractor, and the 114mm reflector to a 102mm refractor.Again ,based on my views with those sizes and types.

So even the 114f8 will be a significant improvement in brightness and resolution over the 70AZ.

Rodrigo Page

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #22 on: January 23, 2018, 02:35:27 PM »
Orion's got a "2nd" SpaceProbe 130ST Equatorial Reflector for $199 that's received excellent reviews from all over internetdom.

If I didn't have my Starblast 6 I would have bought it last week.

Marlin Riewer

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #23 on: January 23, 2018, 06:43:22 PM »
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Orion's got a "2nd" SpaceProbe 130ST Equatorial Reflector for $199 that's received excellent reviews from all over internetdom.

If I didn't have my Starblast 6 I would have bought it last week.

The SpaceProbe would a much better choice than the 127 PowerSeeker; note that the SpaceProbe does have a true parabolic mirror and actual f5 focal ratio .

toughhalrechal

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #24 on: January 25, 2018, 02:23:11 PM »
Addi319

If the Orion SpaceProbe 130ST is a bit over budget, there is also an Orion Starblast 4.5 EQ for $50 less. That is still a very capable scope.Though short it is also NOT a Bird-Jones design.

tranardefa

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #25 on: January 25, 2018, 03:54:38 PM »
Trying to revive this old post, I have a power seeker 80mm EQ refractor and have a opportunity to get a Astromaster 130eq from a co worker. 130 is like new and still carries a warranty. Will there be much difference between them as far as optics. I know neither mount is great but I am really more concerned with the comparison of optics and what I will be able to view. Was reading about obstruction and based on specs will lose the equivalent of 10-15 mm, maybe more. Still a much larger apperture with higher useful mag.

Thoughts, He's moving and needs to get rid of some stuff so I can get it for a good price.

Troy Furlong

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #26 on: January 25, 2018, 05:59:17 PM »
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Trying to revive this old post, I have a power seeker 80mm EQ refractor and have a opportunity to get a Astromaster 130eq from a co worker. 130 is like new and still carries a warranty. Will there be much difference between them as far as optics. I know neither mount is great but I am really more concerned with the comparison of optics and what I will be able to view. Was reading about obstruction and based on specs will lose the equivalent of 10-15 mm, maybe more. Still a much larger apperture with higher useful mag.

Thoughts, He's moving and needs to get rid of some stuff so I can get it for a good price.


I have owned a number of 80mm F/11 refractors like yours and a number of 130mm F/5 Newtonians.. In fact, in theory, I still do. But the refractors are tied up in a laboratory experiment and the Newtonian is on loan. The 130mm Newtonian will definitely show more but it is more finicky, you will need to collimate it, easy to do with the right simple tools, and it will need to cool down to provide the best planetary and double star views.

In a deal like this, the cost is always and important factor: How much is your co-worker asking?

Jon

Malcolm Verano

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #27 on: January 25, 2018, 09:46:56 PM »
The Astromaster 130EQ would be a nice upgrade and still easily managed as regards to using,carrying,storage, and adjusting.You should gain a wider field of view, and somewhat brighter views compared to the 80EQ.Having both scopes will be great.

If the 130EQ is complete and you can get it for half or less of the new price I say go for it!ared to the 80EQ.

afelfillia

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #28 on: January 30, 2018, 06:37:21 AM »
It would be less than 1/2, just seen mixed reviews on this unit, some say it is no better than the 80mm I have.

Tsar Daniels

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Re: Going to a 130mm reflector from a 70mm refractor
« Reply #29 on: January 31, 2018, 02:52:40 AM »
Just be sure the reviews are about the 130EQ with actual parabolic mirror and f5 optics and NOT thew 127EQ which is one of those shorty Bird-Jones compromises.